Data from: The red coral (Corallium rubrum) transcriptome: a new resource for population genetics and local adaptation studies

The question of species survival and evolution in heterogeneous
environments has long been a subject for study. Indeed, it is often
difficult to identify the molecular basis of adaptation to contrasted
environments, and nongenetic effects increase the difficulty to
disentangle fixed effects, such as genetic adaptation, from variable
effects, such as individual phenotypic plasticity, in adaptation.
Nevertheless, this question is also of great importance for understanding
the evolution of species in a context of climate change. The red coral
(Corallium rubrum) lives in the Mediterranean Sea, where at depths ranging
from 5 to 600 m, it meets very contrasted thermal conditions. The
shallowest populations of this species suffered from mortality events
linked with thermal anomalies that have highlighted thermotolerance
differences between individuals. We provide here a new transcriptomic
resource, as well as candidate markers for the study of local adaptation.
We sequenced the transcriptome of six individuals from 5 m and six
individuals from 40 m depth at the same site of the Marseilles bay, after
a period of common garden acclimatization. We found differential
expression maintained between the two depths even after common garden
acclimatization, and we analysed the polymorphism pattern of these
samples. We highlighted contigs potentially implicated in the response to
thermal stress, which could be good candidates for the study of thermal
adaptation for the red coral. Some of these genes are also involved in the
response to thermal stress in other corals. Our method enables the
identification of candidate loci of local adaptation useful for other
nonmodel organisms.